Method of manufacturing magnet and method of manufacturing rotor

Abstract

A sheet-shaped insulating member including a thermoplastic resin fiber and an inorganic fiber is arranged on a surface of a magnet body. The insulating member is compressed while being heated to a temperature higher than or equal to a glass transition temperature of the thermoplastic resin fiber, so that the insulating member is thermocompression-bonded to the magnet body in a state in which the inorganic fiber is elastically compressed. A magnet is thus formed. With the magnet arranged in a slot of a rotor core, the magnet is heated to a temperature higher than or equal to the glass transition temperature of the thermoplastic resin fiber. This causes the inorganic fiber to restore elasticity, so that the magnet is fixed to the rotor core.

The invention claimed is: 
     
       1. A method of manufacturing a magnet, the magnet including a magnet body having a surface covered with an insulating member, the method comprising:
 an arrangement step that arranges, on the surface of the magnet body, the sheet-shaped insulating member including a thermoplastic resin fiber and an inorganic fiber; and 
 a thermocompression step that compresses the insulating member while heating the insulating member to a temperature higher than or equal to a glass transition temperature of the thermoplastic resin fiber, thereby thermocompression-bonding the insulating member to the magnet body in a state in which the inorganic fiber is elastically compressed, and 
 wherein the sheet-shaped insulating member includes insulating members unwound from two rolls that are made by rolling up the insulating members, and 
 the arrangement step arranges the insulating member unwound from one of the rolls on a first surface of the magnet body, and arranges the insulating member unwound from the other roll on a second surface of the magnet body. 
 
     
     
       2. A method of manufacturing a rotor, wherein
 the rotor includes: 
 a rotor core having a slot; and 
 a magnet that is arranged in the slot and includes a magnet body having a surface covered with an insulating member, 
 the method comprising: 
 an arrangement step that arranges, on the surface of the magnet body, the sheet-shaped insulating member including a thermoplastic resin fiber and an inorganic fiber; 
 a thermocompression step that compresses the insulating member while heating the insulating member to a temperature higher than or equal to a glass transition temperature of the thermoplastic resin fiber, thereby thermocompression-bonding the insulating member to the magnet body in a state in which the inorganic fiber is elastically compressed, so as to form the magnet; and 
 a fixing step that heats the magnet arranged in the slot to a temperature higher than or equal to the glass transition temperature, thereby restoring elasticity of the inorganic fiber, so as to fix the magnet to the rotor core, and 
 wherein the sheet-shaped insulating member includes insulating members unwound from two rolls that are made by rolling up the insulating members, and 
 the arrangement step arranges the insulating member unwound from one of the rolls on a first surface of the magnet body, and arranges the insulating member unwound from the other roll on a second surface of the magnet body.